Group policy in a mixed XP/Vista domain environment

Hi all,

Just wanting to know if someone can clear up the questions I have about
mixed environment policies to support Windows XP and Vista.

1) If you have a "common" policy you wish to apply to all
users/workstations, is there a nice method, utility, or even some
documentation that would tell me if any of the policy settings should not be,
or could not be, applied to Vista?

We have a number of existing policies (that don't contain firewall settings
etc - which is a known Vista difference), and would like to apply it to both
XP and Vista. In testing these "appear" to work, but how can I tell whether
all the settings are being applied, and whether there are any settings that
should be seperated out to a Vista-only policy objects etc? DO I just need to
check/compare each and every setting in RSOP?

2) I take it that using WMI filtering is the only way to seperate these
policies? For example XP firewall configuration settings in one policy, and
Vista advanced firewall settings in another using version 6000 as the filter?

3) How can you, or do you even need to, somehow filter user configuration
changes? I would like to apply a number of user configuration policy changes
to both XP and Vista, and I am not sure how to do this. I take it that WMI
filtering will only work on computer configuration policies and/or is not
required in this case?

For example, I would like to use "Folder Reidrection" (which is a user
configuration policy item). In a mixed environement, how would I make this
happen? Particularly as the XP and Vista policy settings for these are
completely different?

Can I just apply both sets of changes to one policy? Will the XP client only
apply the XP settings (because it doesn't understand the Vista ones)? And
will the Vista computer use the Vista settings in preference? Or will Vista
try to apply both and potentially break functionality?

Appreciate any assistance.